Chair iron



23, 1932- H. w. SHELDRICK 1,873,054

CHAIR IRON Filed Sept. 20, 1930 Patented Aug. 23, 1932 UNITED STATES PATENTOFFICE HENRY W. SHELDRIOK, OF,G-ARDNER, MASSACHUSETTS, ASSIGNOR TO COLLIERQKEY- WORTH COMPANY, 'OF GARDNER, MASSACHUSETTS, A CORPORATION OF MASSA-i CHUS ETTS CHAIR IRON Application filed September 20,1930. Serial No. 483,240;

Tilting ofiice chairs are commonly provided with springs which tend to maintain the chair seat substantially horizontal, but as heretofore constructed when such a chair is 'o] tilted, its motion is stopped suddenly at its tachment of the J-washer and to the control and limitation of relative -movement of cer'- tain of the parts.

Fora more complete understanding of this invention, reference may be had to the accompanying drawing in which Figure 1 is a top plan of the chair iron. 1

Figure 2 is a side elevation thereof showing parts of the chair seat and base, to which the iron is applied.

Figure 3 is a vertical section through the spindle portion ofthe iron. 7

Figure 4 is a section on line H of Fig ure 3. a

. Figures 5 and 6 are detail sections on lines 5-5 and 6-6, respectively, of Figure 2...

Figure 7 is a sectionsubstantially on line 7-7 of Figure 1, but showing the parts in chair-tilted position. I

Figure 8 is a similar view but with the ch'airhorizontal and showing a modification.

Referring to the drawing, at 1 are shown side rail or spiderielements which may, if

desired, be of angle section and which support thechair seat shown at 2 in "Figure 2.

These elements 1 are shown as. secured at v when the seat reaches fully tllted position'ias substantiallytheir central portions to a' U- shaped member 5 havingside walls 6 (see Figure 6) and a closed end wall 7. This U-shaped member is pivoted on a rod 8 to side wall portions 9 of a U-shaped support which is shown as having a bottom wall 10 upwardly domed at its central portion as at 11 and through which extends the upper the plate portionlugs 82.

portioii of the chair spindle 12, the upper end of which is shown as riveted over against a bridge plate 13 having upwardly turned end flanges 14 secured to and between the walls 9. The pivot 8 for the chair-supporting member passes throughthe walls 6'and 9 and the flanges 14:, and the elements 1. By this construction the chair seat-supporting member comprising the 816- 1 ments 1 and the'parts carried therewith are supported for tilting 'mov ement from the horizontal seat-supporting position shown in Figures 2 and 8. The extent of this motion may be limited by stop portions T20 struck inwardly from the wall members 6 between stop portions 21 struck outwardly fromthe material of the walls 9. The chair. seat is normally held in horizontal position I To this end a;-- screw rod'25 is shown as extended through by resilient holding means.

an opening through the wall member 7 and having its head bearingat itsinner end against a U-shaped yoke member 27 which secured to the inner faces of the walls 9 as may: have a channel cross section in its intermediateportion and which is,,pivotally' atjQLbelow the seat proper. The member i 27 is thus pivoted out of line with but paral lel to, the seat pivot rod 8. With'this arrangement asmall initial movement of the seat from its central position produces considerable motion-of the spring so that the centering action of the spring is increased; s

The outer threaded end of this rod 25v has thereon a nut 28 having an actuatinghand wheel 29 at its outer end, this nut pressing against a spring seat member 30 which houses the outer ends'of coil springs 3l ,fthe inner'ends ofwhich engage the outer face of 7 surrounding centering In order that there may be no severe shock F-igure'and also in Figure 8 this means may comprise leaf springs 35, each fixed at one end as by the rivets 36 to thefltop flange $7 of one of the elements land provided at its free end with a tongue portion 38 projecting through an opening 39 in the flange 37 and positioned to strike upon the upper edge portion 40 of the flange 14 or of the upper edge of the side wall 9 as the seat support having been substantially tilted approaches its fully tilted'position, thus to deflect the spring 35, as shown in Figure 7, and add an additional yielding resistance to the tilt ing of the seat. spring 35 or in addition thereto, if desired, springs formed to present increased rate of resistance to the tilting of the chairlias it approaches its limit of tilting position may be employed in place of the coil springs 31 shown in Figures 1, 2 and 7. For example, such springs may comprise conical volute springs such as shown at 45 in Figure 8.

These springs have portions of different diameters, the portions of small diameters producing a greater resistance to the tilting movement than the coils of larger diameter. Thus "as such springs are compressed the larger coil portions bring up against each ing movement. as well the'spring 45 of the conical volute ber.

other in the initial stages of movement, whereupon the smaller coil portions are successively brought into action and exert an increasingly heavy resistance to further tilt- In Figure 8 the spring 35 type are employed.

The spindle 12 hereinbefore referred tois externally threaded at its upper portion only, as shown best in Figure 3, and on this threaded portion is engaged a nut 50 provided with the usual bell member 51 secured at its upper end thereto and housing a J -washer indicated generally at 52 and the upper end of a sleeve 53 which may be supported in thebase member 54 of the chair which is provided with the supporting leg 55. While the J-washer may be of any desired type, it is shown as a combined J-washer and ballbearing as shown and claimed in the application for patent of Collier and Sheldrick Serial Number 451,938,

fi'led'May 13, 1930. As is customary with J- washers it is provided with a suitable spline 54 (see Figure 4) slidable in, a key slot 55 extending lengthwise of the-spindle Hand to its lower end.

The upper portionof the sleeve 53is shown as provided with a peripheral groove '56 within which may be removably engaged the inner end of a screw 57 which 15 passed through an opening 58 in the lower flange 59 of the bell member 51 and is threaded through a cross memberor bar 60 having itsends se cured as at 61 to the flange 59 of the bell mem- This permits relative rotation between the spindle and sleeve and also ready disassembly thereof as for ease in packing and shipping. This bar 60 may be of such shape In place of this auxiliary.

assembly and then secured in place to prevent subsequent removal of the, J-washer.

From the foregoing description of certain embodiments of this invention, it should be evidentcto those skilled in the art that various chan es and modifications may 'be-made without departing from the spirit or scope of this invention as defined by the appended claims. I

I claim: 7 p

1. In combination, a supporting member, a seat-carrying -member pivoted to said supporting member for tilting movement away from horizontal seat position, a leaf spring fixed at one end to one of said members, and

anelement carried by the other of said members in position to deflect the free end of said spring only when said seat-carrying member is tilted to a substantial extent.

2. In combinatioma support, a 'seat-carrying member pivoted to, said support for tilting movement away from horizontal seat position to a limited extent, resilient means for opposing such tilting throughout its range,

and other means for yieldingly opposing such tilting movement ad acent to its limit only.

been tilted to a predetermined position to flex said springs on further tilting of said member.

4. I In combination, a spindle externally threaded at its upper portion-onlyand having a key slot extending to its lower end, a nutengaging the threaded portion of said spindle,- a sleeve surrounding said spindle and having a peripheral groove at its upper end, a

J-washer between-said nut and sleeve and "having a spline engaging in said groove, re-

movable means carried by said nut engageable in said peripheral groove for retaining said sleeve onsaid spindle, andfa cross member carried by said, nut located beneath said J-washer for preventing the removal of said .J-washer from the lower endofsaid' spindle on removaliof said sleeve.

5. In combination, a spindle externally threaded. at its upper portion only and .havf ing a key slot extending to its lower end, a nut engaging the threaded portion of said spindle, a bell member fixed to said nut, a

J-washer on said stem beneath said nut and,

within said bell member and having a spline engaging in said groove, and a-bar having both ends fixed to the inner face of said bell member and a middle portion located in a position beneath said J-washer to prevent said J-washer from being removed at the lower end of said spindle.

6. In combination, a support having spaced side walls, a seat-carrying member having spaced side walls pivoted to said support walls and a connecting portion joining said member side walls, a U-shaped yoke member pivoted at its sides to the sides of said support, a rod fixed to said yoke member and extending through an opening through said connecting portion, a spring seat on the outer end of said rod, and spring means positioned between said spring seat and connecting portion.

In testimony whereof I have affixed my signature.

HENRY W. SHELDRICK. 

